Hyundai Forum: Hyundai Performance Forum banner

1 - 20 of 24 Posts

·
Registered
Joined
·
1,415 Posts
Discussion Starter #1
I hear WeaponR sux, AOS isnt too good, KORE is great, SR's will be the best... now what makes certain CAIs better then others? I would like to know... is it material, weight, placement, location, filter.... WHAT?! <img src=/images/forums/snitz/cool.gif width=15 height=15 border=0>


<hr noshade width=60% size=1 align=left>Just cuz you're jealous...
My friend is a lesbian.<img src=/images/forums/snitz/wink.gif width=15 height=15 border=0>
I love Cass, my Aussie hunny. <img src=/images/forums/snitz/thumbup.gif width=25 height=18 border=0>
HP.com #1 Pimp
 

·
Registered
Joined
·
2,951 Posts
Ok time to set ya straight kid.

1. Weapon R, Your correct about, might aswell just get a cone filter.
2. I have AOS CAI, Its a awesome set up. I wouldn't get it if I new it was crap.
3. Kore from what I heard is a good intake, but can't afford it.
4. Shark racings, I heard was good too, but probably expensive.

All in all, they are good CAI's besides Weapon-R's, Location and placement is probably what I would go with, my AOS cai locates itself near the front bumper, and does a excellant job of sucking in the cold air that is required. It even sounds good.


<hr width=60% noshade size=1 align=left>Your death is comming on swift wings, and I am the rider.
<img src="http://israfel.org/auron/fmv02.jpg" <img src="http://israfel.org/auron/sprite4.gif"
 

·
Registered
Joined
·
1,415 Posts
Discussion Starter #3
Ok kiddo.... still doesnt answer my question <img src=/images/forums/snitz/tongue.gif width=15 height=15 border=0>

I know placement is a key thing as well, but does material and crap also make an effect on the CAI? I know the cone does, but what about material, how thick it is, how wide the hole if for air... what??? <img src=/images/forums/snitz/oogle.gif width=15 height=15 border=0>


<hr width=60% noshade size=1 align=left>Just cuz you're jealous...
My friend is a lesbian.<img src=/images/forums/snitz/wink.gif width=15 height=15 border=0>
I love Cass, my Aussie hunny. <img src=/images/forums/snitz/thumbup.gif width=25 height=18 border=0>
HP.com #1 Pimp
 

·
Registered
Joined
·
2,951 Posts
Personally, I don't think you would make any other CAI other than metal piping unless its custom, AOS CAI piping is about as thick as a floppy disk, I'd say the intake whole for air is about 2.5 inchs wide. give or take.


<hr width=60% noshade size=1 align=left>Your death is comming on swift wings, and I am the rider.
<img src="http://israfel.org/auron/fmv02.jpg" <img src="http://israfel.org/auron/sprite4.gif"
 

·
Registered
Joined
·
138 Posts
Well, one answer may be improper length, a intake pipe can be tuned. It takes a lot work to tune a intake pipe length, because you have to tune it for the pressure waves, but with a ram effect, it is less critical. When you purchase a new filter housing, talk to a good filter manufacture, one that has race and engine tuning experience. I have found some of the best to be in europe developing filters for formula one and rally. That is wear I aquired my filter setup. Here is simple example on tuning.

Helmholtz's Theory

The idea here is to continue to use the tuned port advantages in the plenum and intake pipe. Actually, tuned ports are Helmholtz resonators themselves. So you can rear the Tuned Port Basics page to get an idea of how it all works, this page will just take that system further up in the intake track. To make it simple, lets say that there is one throttle bore for a 4 cylinder engine. There will be 2 induction pulses through the throttle bore per revolution. When the air pulses through the throttle bore, is causes a negative pressure wave traveling through the intake pipe. Once this pulse reaches the open end of the pipe (usually at the air cleaner), it will invert to a positive pressure wave. If we can time this wave to arrive back at the plenum to boost pressure when it's needed the most, we may see a power increase. The Helmholtz resonator theory does work well, however, it is limited to how many cylinders can operate off a single plenum. To be effective, no more than 4 cylinders should be used in a single plenum. This set up is very effective on 6 cylinder engine with two plenums, each plenum feeding 3 cylinders. To make matters worse, the cylinders must be even firing, so simply dividing banks of a V6 or V8 will not work unless the banks each fire evenly. For a V8, the best solution is to use a 180 degree crankshaft to even out the firing order of each bank. Then the Helmholtz resonator can be applied as if it were a pair of 4 cylinders. It is possible to see small gains at low rpm with using one plenum for 8 cylinders, but this will usually lead to a reduction in top-end power. There are 3 tunable aspects of the Helmholtz resonator, the plenum volume, intake ram pipe, and intake ram pipe diameter.

Intake Ram Pipe Diameter

This is the easiest to figure out. The velocity in the plenum intake pipe should not be higher than 180 ft/sec at maximum rpm. The formula to figure out the diameter pipe that should be used is for a given velocity is:

D = Square Root of (CID × VE × RPM) ÷ ( V × 1130)

Where:
D = Pipe Diameter
CID = Cubic Inch Displacement
VE = Volumetric Efficiency
V = Velocity in ft/sec

If you're dealing with liters, change CID to liters and the constant to 18.5 so the formula will look like this:

D = Square Root of (Liters × VE × RPM) ÷ (V × 18.5)

An example for a 153 cubic inch 4 cylinder with a 85% VE, revving to 6000 rpm would and a desired 180 ft/sec air speed though the intake pipe would look like this:

D = Square root of (153 × 0.85 × 6000) ÷ (180 × 1130) = 1.96

You would need an intake pipe that has a 1.96" inside diameter to have 180 ft/sec air velocity at 6000 rpm for that engine. In other words the engine would need a little over 3 square inches of intake pipe area.

Plenum Volume

There is not going to be a simple answer to the needed plenum volume for a given application or rpm range. The good thing about plenum volume is that there is a pretty wide range that it can be and still be effective, so general rules work well. The following guide lines are for engine operating in the 5000-6000 rpm rage. V8's with one large plenum feeding all 8 cylinders does not work all that well as far as the Helmholtz resonator goes, but if this is the case, plenum volume should be about 40-50% of total cylinder displacement. For a four cylinder 50-60% works well. For 3 cylinders (6 cylinder engine with two plenums), each plenum needs to be about 65-80% of the 3 cylinders it feeds. If a boost is desired in a higher rpm range, closer 7000-7500 rpm, the plenum will need to be 10-15% smaller. To get a boost in the 2500-3500 rpm range, it will need to need about 30% larger. The plenum size of a Helmholtz resonator may go against the typical plenum size rules, but the rules change when the resonator is being used. The whole Idea of a plenum is to allow the gases to slow down and gain density. The Helmholtz plenum makes a dense charge by use of pressure waves, in the same way tuned port intake runners work. This plenum sizing method does not apply to engines that to not use a tuned intake pipe. Many engine simply have the air cleaner assembly directly on the carb or throttle body having very little intake length. In those cases the Helmholtz resonator system does not work.

Intake Ram Pipe Length

The last thing to adjust is the length of the intake ram pipe. It is possible to make an adjustable pipe that can be made longer or shorter for testing purposes. For a starting point figure a 13" long pipe will help at about 6000 rpm. For each 1000 rpm drop in rpm add 1.7" and subtract 1.7" per 1000 rpm increase. This is just a starting point. The inlet of the pipe should have about a 1/2" radius for smooth flow. Once you get a base line, you must do a power pull and get a baseline. This can be done at the track or on a dyno. They try moving the pipe 1/2" in either direction as see how power improves. The dyno may be a little deceiving, since peak hp my go up but average power may drop. Track testing will be best, since you will be testing in actual racing condition and can tune the pipe for the best times. It is usually best for average power if the intake ram pipe is tuned about 1000 rpm lower than the intake runner length.

Multiple Intake Ram Pipes

Most engines will have more than 1 throttle bore feeding the cylinders. In this case you must figure out the total area of intake pipe needed to figure out what size each pipe should be. In the first example, the 4 cylinder needed a 1.96 diameter intake ram pipe. If that particular engine had a two barrel (or two carbs). You would need two pipes each one having 1/2 the area of a 1.96" pipe. First off, a 1.96" diameter pipe has a total of 3.02 square inches. So we're be looking for pipes that each have 1.51 square inches of area. Using the formula for finding the area of a circle in reverse, you come up with 1.39" diameter. So a pair of 1.39" diameter pipes will act the same as a single 1.96" pipe.



<hr width=60% noshade size=1 align=left>
 

·
Registered
Joined
·
1,415 Posts
Discussion Starter #6
<img src=/images/forums/snitz/eek.gif width=15 height=15 border=0><img src=/images/forums/snitz/eek.gif width=15 height=15 border=0><img src=/images/forums/snitz/eek.gif width=15 height=15 border=0><img src=/images/forums/snitz/oogle.gif width=15 height=15 border=0><img src=/images/forums/snitz/oogle.gif width=15 height=15 border=0><img src=/images/forums/snitz/eek.gif width=15 height=15 border=0><img src=/images/forums/snitz/eek.gif width=15 height=15 border=0><img src=/images/forums/snitz/eek.gif width=15 height=15 border=0>


<img src=/images/forums/snitz/thumbup.gif width=25 height=18 border=0>


<hr width=60% noshade size=1 align=left>Just cuz you're jealous...
My friend is a lesbian.<img src=/images/forums/snitz/wink.gif width=15 height=15 border=0>
I love Cass, my Aussie hunny. <img src=/images/forums/snitz/thumbup.gif width=25 height=18 border=0>
HP.com #1 Pimp
 

·
Registered
Joined
·
9 Posts
BTW...AEM is now making a CIA for the Tiburon! It's about time! <img src=/images/forums/snitz/thumbup.gif width=25 height=18 border=0>


<hr width=60% noshade size=1 align=left>-"a car is an extension of your personailty...it reflects who you are..."
-Island Street Performance forever!
-2001 Tiburon:
Weapon-R intake
Unorthodox pullies
MBRP catback exhaust
Eibach springs
 

·
Registered
Joined
·
7,118 Posts
I wonder how hard it is to tune a variable intake like the ones used in the 7seris BMW and the Hyundai Centinial.




<hr width=60% noshade size=1 align=left><img src="http://jvx.itgo.com/untitled.jpg"></img>
1.6 DOHC 16v
5-speed
[email protected]
www.geocities.com/accentpage
"Ew Ei Ew Ah AH big bang.. wallawalla.. bing bang..
Ew Ei Ew ah ah Bing Bang wallawalla bing bang"
 

·
Registered
Joined
·
21,319 Posts
To simplify that long but informitve post.

The filter obviously makes a difference.
You do have different types of filters and different materials used but that is a hole other post.

As far as the intake piping goes.

The material used makes a difference cause some conduct heat better then others. For instance carbonfiber does not conduct heat as well as say a chrome piece of metal. So the carbon fiber would be a better matieral used.

The design

The less bends the better and the less pieces the better. This allows air to flow faster and smoother.

The location of the filter. In needs to be in a place that it can pull the coolest air possible. Also if it it is in an area that it can get air forced into it that is even better.

And probably the most minor thing that makes a difference is weight of the intake itself. A lighter intake is better cause of weight reduction but considering that their will not be that much difference in weight between intakes don't worry to much about that. The other things will make more of a difference.
(ex yes the weaponR intake is probably lighter than most cause of its size but i would not choose it over the others due to the location of the filter.)


<hr width=60% noshade size=1 align=left><img src="http://www.transfans.com/logospin.gif"></img><b>I absolutely positively abhor and verbally bitchslap anyone who starts quoting me their entire car mods as some sort of "Stage.~RED~</b><img src=/images/forums/snitz/wink.gif width=15 height=15 border=0>
 

·
Registered
Joined
·
1,415 Posts
Discussion Starter #10
what if I got 3" opening pipping of PVC and a K&N filter?? Would that work good or no?? <img src=/images/forums/snitz/thumbup.gif width=25 height=18 border=0>


<hr width=60% noshade size=1 align=left>Just cuz you're jealous...
My friend is a lesbian.<img src=/images/forums/snitz/wink.gif width=15 height=15 border=0>
I love Cass, my Aussie hunny. <img src=/images/forums/snitz/thumbup.gif width=25 height=18 border=0>
HP.com #1 Pimp
 

·
Registered
Joined
·
1,893 Posts
To sum up again that cool post by HRD.

An intake pipe needs to be tuned. Too LONG of a pipe, will hurt top end, too short of a pipe will kill low end.

To large of a pipe will Kill low end, to small of a pipe will kill High end.

To many bends, or simply severe bends will slow the air down, and make a short pipe act like a longer pipe.

Bare metal (uncoated) intakes tend to heat up, which tends to heat the incoming air, defeating the purpose of the Cold air porton of the intake, however if the intake tube is shaped/tuned right, it can still show gains.

If you wanted the downside of each intake currently on the market.

Speedstates only fault is filter placement. Placing the filter in the hot engine bay behind the radiator.

KORE/MHP design has 90 degree bends which slow down air, and placing the filter in the fenderwell, which is technically a low pressure area (unless you leave the fog light/light covers out).

AEM/Injen...have not seen them, cannot comment

SR/Random Special. Filter location in fenderwell, which is technically a low pressure area (unless you leave the fog light/light covers out, or have Z-Shark Fenders).

Weapon-R Intake filter is right were stock airbox is. Sucks in hot engine compartment air.
Weapon-R Ram Air. Intake filter sits right were stock airbox is, "ram Air" pipe is actually 2.5" flexable dryer hosing, that is HORRIBLE for air flow. You then have to route this to somewhere that has High pressure air to get the Ram Air Effect. Also, the Weapon-R filter is not sealed with the "Ram Air" kit, allowing it to suck air around the base of the device (Hot engine compartment air), and/or allowing your "ram air" effect air to pass over the filter and out into the engine compartment (worthless).(For a Ram Air setup to have any value, it must pressurerize an airbox. The weapon-R setup cannot build up any pressure, as the air just leaks out into the engine comparment)

4DoorGL is Planning a CAI showdown, and I will be helping him. He plans on testing all the current CAI's on the market. All in one day, on one car, on one dyno. Each CAI will be tested twice. This should give everyone repeatable/accurate numbers, and allow everyone to make informed decisions on purchasing a CAI.


<hr width=60% noshade size=1 align=left>Leave it to Random to Needlessly complicate things.
 

·
Registered
Joined
·
1,415 Posts
Discussion Starter #12
Where can I get this.... Random special?? <img src=/images/forums/snitz/tongue.gif width=15 height=15 border=0><img src=/images/forums/snitz/wink.gif width=15 height=15 border=0>


<hr width=60% noshade size=1 align=left>Just cuz you're jealous...
My friend is a lesbian.<img src=/images/forums/snitz/wink.gif width=15 height=15 border=0>
I love Cass, my Aussie hunny. <img src=/images/forums/snitz/thumbup.gif width=25 height=18 border=0>
HP.com #1 Pimp
 

·
Registered
Joined
·
1,893 Posts
<BLOCKQUOTE id=quote>quote:<hr height=1 noshade id=quote>
Where can I get this.... Random special??
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote>

Drive by my house and I can make one for you. I had posted the instructions, parts needed and photos some time ago. It takes about $50 in parts to make, including heat wrap. Save $20-$25 by leaving off the heat wrap. Increase the cost by $20-$50 if you want an expensive K&N filter rather than a cheaper generic cone filter.


<BLOCKQUOTE id=quote>quote:<hr height=1 noshade id=quote>Told you. Random is cool as hell in person, even if he is a dick on the net (j/k).
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote>

Leave it to Random to Needlessly complicate things.
 

·
Registered
Joined
·
130 Posts
Hey Random, where are you located? (city)

TIA




<hr width=60% noshade size=1 align=left>Ralph E Boy
2001 Elantra GLS
front strut bar, more to come
 

·
Registered
Joined
·
1,893 Posts
<BLOCKQUOTE id=quote>quote:<hr height=1 noshade id=quote>
Hey Random, where are you located? (city)
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote>

El Segundo, CA (1st city south of LAX airport)


<hr width=60% noshade size=1 align=left>quote from 4DoorGL: <b><i>"Told you. Random is cool as hell in person, even if he is a dick on the net <img src=/images/forums/snitz/wink.gif width=15 height=15 border=0> (j/k)" </b></i>

Leave it to Random to Needlessly complicate things.
 

·
Registered
Joined
·
138 Posts
When designing or building a intake system, you need to account for air the consumption of 720 degrees of engine rotation. For the 2.0ltr it is approx. .055cuft per engine cycle., which that equates to 191cfm per minute. The plenum volume is about .030cuft, excluding runner length. That mean there is .025cuft of air that has to be found in the intake pipe. To get that .025cuft you could take and make a long 3in pipe, but if length is to long resriction increases and you have to account for filter restriction also. The filter restriction can be found using a standard vacuum gauge and then you can calculate flow losses over the given length of pipe. When the throttle is suddenly openedthere is a moment that the intake pipe is under added negative pressure, because the volume of air in the pipe has been consumed and the length of pipe and filter is adding the restriction causing the pressure drop. One way to counter this is to use a shorter larger dia pipe that has the required volume, to reduce the lag of the air flow caused by the longer length of pipe and filter. I have found this has been the best fix outside of design and tuning a intake on developmental simulation software or using dyno trial and error.


<hr width=60% noshade size=1 align=left>
 

·
Registered
Joined
·
21,319 Posts
Uhm geezus herbert krist!!!!!!!!!!!!

Either you are realy freakin smart or you know how to copy and paste.

Can you translate that into english so we can all understand what the hell you just said?<img src=/images/forums/snitz/laugh.gif width=15 height=31 border=0>


<hr width=60% noshade size=1 align=left><img src="http://www.transfans.com/logospin.gif"></img><b>I absolutely positively abhor and verbally bitchslap anyone who starts quoting me their entire car mods as some sort of "Stage.~RED~</b><img src=/images/forums/snitz/wink.gif width=15 height=15 border=0>
 

·
Registered
Joined
·
138 Posts
Basically get some flow numbers for the filter you purchase. Using the vacuum is a cheap way of measuring restriction on the filter and intake pipe. The lower the reading less restricton, it helps if you have a digital gauge that can read to at least .01 in. vacuum. Try to go with as short of a pipe as possible and increase pipe dia to get the required volume needed. A person can play with pressure pulses in the intake pipe to tune it, but it gets really complicated quick. I have gotten some of my knowledge from my job in engine research and development, this is my first import project.
 

·
Registered
Joined
·
1,893 Posts
Or, you could design an intake like Red had. It had a built in "air chamber" to increase the volume.

It was 2.5" at the TB opening, then jumped to 5" after the 90 degree bend, then gently tapered down to 3" at the filter. It used that large diameter area as an air chamber, and the diameter change from 5" to 3" serves to increase the air velocity.


<hr width=60% noshade size=1 align=left>quote from 4DoorGL: "Told you. Random is cool as hell in person, even if he is a dick on the net <img src=/images/forums/snitz/wink.gif width=15 height=15 border=0> (j/k)"

Leave it to Random to Needlessly complicate things.
 
1 - 20 of 24 Posts
Top